1) Field of the Invention
The invention relates to a device for heating liquids, comprising a first liquid container, a second liquid container, which second liquid container is at least partially filled with an intermediary liquid, and a heating element coupled to the second liquid container, wherein heat transfer from the heating element to the liquid for heating takes place at least substantially via the intermediary liquid. The invention also relates to an assembly for use in such a device.
2) Description of the Related Art
Devices for heating liquids have been known for a long time. The applications of these devices can also be very diverse in nature. Such heating devices are thus already applied for instance as, or as component, in water kettles, dish washers, washing machines, coffee-making machines and the like. A known drawback of the known devices which are (partially) adapted to heat liquids is the deposition of contaminants, such as limescale and soap residues and the like, on the heating element. The heat transfer from the heating element to the liquid for heating is considerably impeded by the deposition of contaminants on the heating element. Heating of the liquid to a desired temperature will therefore generally require more time and energy, which is costly and may be accompanied by overheating of the heating element.
An improved heating device is disclosed is the U.S. Pat. No. 4,803,343, comprising a container for a liquid to be heated, an elongated receiver partially filled with a working fluid, and a heating element substantially positioned within said receiver. During operation, the heating element will evaporate the working fluid to vapour bubbles which bubbles will subsequently condense at a wall of the receiver, thereby generating condensation heat for heating the liquid. Heating of the liquid for heating via the working fluid has the substantial advantage that the heating element per se remains substantially unaffected, since direct physical contact between the heating element and the liquid for heating is prevented. However, heating a liquid by means of this device has as major drawback to pass off relatively slowly, wherein a considerable amount of energy is required to initiate (sufficient) bubble formation to heat the liquid to a desired temperature.
The invention has for its object to provide an improved heating device with which a liquid can be heated in a relatively quick and energy-saving manner.